Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 69 users online :: 4 registered, 0 hidden and 65 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

3d printer possible backlash?

All non-spudgun related discussion goes here such as projects, theories, serious questions, etc. All "off-topic" posts (aka useless posting, determined by moderators) will be removed.
Sponsored 
  • Author
    Message

3d printer possible backlash?

Unread postAuthor: CS » Tue Nov 18, 2014 4:49 am

Pictures are up side down, sorry.

That orange line is the top of the print. So that means I have backlash left-to-right, right? Just wondering, might have to delve deeper into it to see where I could have slack in the system.

So a quick reality check of which way the backlash is happening would be much appreciated.
  • 0

Attachments
20141118_014125.jpg
20141118_014109.jpg
User avatar
CS
Donating Moderator
Donating Moderator
 
Posts: 1897
Joined: Fri Feb 18, 2005 5:32 pm
Location: Southern Utah
Country: United States (us)
Reputation: 4

Re: 3d printer possible backlash?

Unread postAuthor: sudpuzzer » Tue Nov 18, 2014 9:23 am

What printer do you have? What are the drive mechanisms for the axis? If you have belts, you could try increasing the tension on them slightly. It looks like you have a problem in both axis since the gaps appear on an angle to both X and Y. You could also try reducing the print speed.
  • 0

Image
User avatar
sudpuzzer
Specialist
Specialist
 
Posts: 52
Joined: Tue Oct 02, 2012 5:11 pm
Reputation: 9

Re: 3d printer possible backlash?

Unread postAuthor: mobile chernobyl » Tue Nov 18, 2014 10:57 am

Similar to Sudpuzzer's request - what printer, firmware (version) and slicer program are you using?

Like what sudpuzzer was saying - make sure your drive mechanisms are tight and true - but not overly tight as that can cause missed steps and completely ruin your print. - there are guides and general recccomendations on reprap.org about how tight to have your belts/cables and friction joints in order to achieve accuracy without contributing to excessive friction.

Another thing to consider is what firmware version and what slicer program and version you are using. Something as simple as a bug in the slicing algorithm can easily lead the the gaps you are seeing between the inner wall and the infill you are seeing. Slic3r in previous versions was notorious for this gap. Switching slicers to something like Kisslicer or other options can allow you to see if that is the problem. Also - if you are generating your g-code with slicer in Auto mode, you might want to switch to manual and adjust infill values - such as percentage or feed rate of the extruder (to fill those gaps better).

So many variables can effect the results to get the affect you're seeing - browse reprap.org for a while and you'll get some insight for sure.
  • 0

User avatar
mobile chernobyl
Colonel
Colonel
 
Posts: 732
Joined: Sun Dec 03, 2006 11:53 am
Reputation: 9

Re: 3d printer possible backlash?

Unread postAuthor: sudpuzzer » Tue Nov 18, 2014 11:15 am

^ seconded.

I assumed you were having a hardware issue, but it did cross my mind that it could simply be a poor slice. For example, in my own Slic3r settings, I have specified manual extrusion widths through trial and error, as well as tweaking the extrusion multiplier slightly. In my opinion, that's the worst part of getting prints to look good, tinkering with the slicing settings.

I guess the point is that it could be a variety of factors causing what you observe, so as much information as you can provide about your setup would be very useful.
  • 0

Image
User avatar
sudpuzzer
Specialist
Specialist
 
Posts: 52
Joined: Tue Oct 02, 2012 5:11 pm
Reputation: 9

Re: 3d printer possible backlash?

Unread postAuthor: CS » Thu Nov 20, 2014 6:59 am

3d printer - xyz da vinci 1.0
drive mechanism - belts
programs - sketchup->xyzware

I have tried playing with the belt tension, to no avail. Although I am sure it is a mechanical, not software issue.
It looks like you have a problem in both axis since the gaps appear on an angle to both X and Y.


Image

This is a illustration of x axis backlash. So rotate it 90 degrees to illustrate an y axis backlash. With those gears in front of me the inner circle looks almost identical to the illustration.

...but. The errors in the gear teeth themselves puzzle me. In one diagonal direction you get overly skinny teeth, and in the other diagonal you get overly fat teeth. So at this point I almost wonder instead of a pure backlash problem, could the square structure of the rails actually be more like a parrelogram? I know this is hard to conceptualize, but if it were a pure backlash problem you would expect each tooth triangle to be non-symmetrical. However the teeth are indivually symmetrical, but change in width as you go around.

I've been away from my printer for a few days, but I should give more insight within the day.
  • 0

User avatar
CS
Donating Moderator
Donating Moderator
 
Posts: 1897
Joined: Fri Feb 18, 2005 5:32 pm
Location: Southern Utah
Country: United States (us)
Reputation: 4

Re: 3d printer possible backlash?

Unread postAuthor: wyz2285 » Sun Nov 23, 2014 11:16 am

http://www.thefirearmblog.com/blog/2014 ... r15-lower/
The guy that printed these used the same printer as yours. Pretty cool.
  • 0

CpTn_lAw wrote::D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
User avatar
wyz2285
Major General
Major General
 
Posts: 2244
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Country: Portugal (pt)
Reputation: 12

Return to Non-Spudgun Related Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot]

Reputation System ©'